I can understand why people take kids to wetherspoons to eat, its not bad food, comfortable atmosphere and its got a decent bar. I don't class wetherspoons as a pub during the day, its hardly even a pub at night, at least from my experience of the one in Lancaster. Its more of a place for a social drink or two, quiet and good for chatting.
As for not being able to drink when you've taken your child out to wetherspoons, I think they have their rules right. During the times that children are allowed in there it is a place to eat or socialise, not to get drunk! Its forcing parents to be responsible whilst in their bars and its a good idea.
As for kids having no fun at pubs and clubs, I used to get taken to Springhill Club when I was younger and loved it, everyone used to take their kids there! I'm still friends with some of the kids I met there aswell, and thats the only way we knew eachother
happy times.